Many service provider networks employ a set of provider edge (PE) routers that define the provider side edge of the network. Each PE router interfaces with customer premises equipment (CPE) located at one or more customer sites served by the PE router. Service provider networks often provide virtual private network (VPN) services to interconnect different customer sites in a secure and private manner. To implement one or more VPNs between these customer sites, the PE routers communicatively coupled with the CPE at the different customer sites exchange routing information (also referred to as routes). Because each PE router can be connected to many CPE at many different customer sites, and each of these CPE can be part of a different VPN interconnecting with other CPE(s) at some other customer site(s), each PE router may support multiple VPNs and potentially need to communicate routes to any of the other PE routers in the service provider network. In smaller networks, a full mesh of PE routers is implemented to enable any PE router to exchange routes with any other PE router in the network. However, because full mesh implementations may not scale well, larger networks often employ route reflectors to exchange routes between PE routers.
In at least some service provider networks, a route reflector connects to the PE routers in the service provider network using interior border gateway protocol (iBGP) sessions. Each PE router uses iBGP to send routes to the route reflector for each VPN supported by the PE router. Additionally, each PE router uses iBGP to receive via the route reflector the routes from other PE routers in the network for each VPN the PE router supports. In an iBGP implementation, a route is a collection of objects, including a prefix and a set of route parameters, and a typical route reflector can maintain hundreds of thousands, or even millions, of routes.